Sweaty Synthetic Clothes Smell Worse, Says Science

If you're doing sweaty athletics, your clothes are going to end up smelly. But have you noticed some clothes end up much smellier? You're not crazy; science shows synthetic clothes create the perfect environment for the smelliest sweat bacteria to get funky.

In what was likely one of the more pungent research papers submitted to the journal Applied and Environmental Microbiology, a research team at Ghent University studied the relative stinkitude of different sweat-soaked clothes. Twenty-six volunteers, evenly split between men and women, wore either cotton, polyester, or cotton/synthetic workout clothes during a one-hour spin session. Post-exercise, their sweat-permeated clothes were put in individual airtight bags overnight to stew.

The next day, trained (and very unlucky) noses were asked to rate the bagged exercise clothes from least to most rank. And as Scientific American puts it, "the polyester shirts were indeed more musty, sour, and ammonia-like than the cotton."

There's a fascinating scientific reason for that. DNA analysis showed that the most-common bacteria present in the marinated meshes belonged to the Micrococcus family. These types of bacteria are only a minor player in human sweat, and they don't like cotton. But the open-air lattice that makes synthetic exercise wear so gloriously breathable also provides the perfect Micrococcus home, where the bacteria chows down on the long-chain fatty acids present in sweat, turning them into shorter compounds that are way stinkier than your actual sweat.

Now you know why your gym clothes smell way more disgusting the day after. Those synthetic blends may be great for wicking sweat away from your body but once your workout is over, they become a veritable buffet for sweat-snacking bacteria. [Scientific American]